Metal cutting tool



Jan. 12, 1943. o. A. PALM 2,307,853

METAL CUTTING TOOL Filed March 28, 1942 v INVENTOR.

OSCARAFPALM' ms ATTORNEY METAL ml a EL Oscar A. Palm. Demis, Application March. as, 1942, N0, :1

' 3 claims. (or. zen

My invention pertains to metal cutting tools such as reamers, milling cutters and the like, and more particularly to an improved method of and construction for mounting and securing cutter blades in a tool body or shank.

It is an object of my invention to provide an improved method of and construction for firmly securing one or more cutter blades of expensive high speed tool steel'in a recess in a tool body of a cheaper and softer metal such that tools can be manufactured more rapidly and more economically. v

It is also an object of my invention to provide an improved method of and construction for firmly mounting and securing one or more blades or" hard high speed tool steel in a'tool body or shank of a cheaper and softer metal in nonfused relation and without the application of heat, as in weidingor brazing, adversely effecting the temper, hardness and durability of the cutter blades so that tools may be economically and quickly manufactured having improved cutting characteristics and substantially longer life and greater durability.

Further objects and advantages are within the scope of my invention, such as relate to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combinations of parts, elements per se, and to economies of manufacture and numerous other features as will be apparent from a consideration of the specification in conjunuction with the drawing disclosing specific embodiments of my invention, similar reference characters being applied to corresponding elements throughout, and in which:

Fig. 1 is a side elevational View showing a metal cutting reamer constructed in accordance with my invention;

Fig. 2 is an end elevational view of the reamer showing the ends of the tool body and the cutter blades;

Fig. 3 is an enlarged plan view of the recessed side of a single cutter blade showing the recesses or open cut out portions provided therein before the blade is mounted in the tool body;

Fig. 4 is a similar view of acutter blade showi ing a different modification of the cut out recesses;

Fig. 5 is an end elevational view of the retion of each cutter blade showing how the metal of the tool enters to prevent either radial or axial displacement of the blade;

Fig. 7 is a greatly enlarged fragmentary view of a portion of Fig. 6 showing only one of the cutter blades secured permanently in a portion oi the tool body: and Fig.- 8 is an enlarged fragmentary sectional view taken longitudinally on line 8--8 in Fig. 6.

Referring more specifically to Figs. l, 2, and 3 of the drawing, I have illustratively disclosed my invention embodied-in a metal cutting reamer' comprising metal cutter elements ll made of an expensive high speed tool steel mounted in an elongated tool body or shank It made of a softer ing mech. There are several different metals suitable for making such high speed metal cessed tool body before the blades have been in- 6-6 of Fig. 1 through a recess or cut out poras cutting elements H but, as such metals are expensive and dlflicult to obtain, it is very desirable and a s r to mount these precious elements in such a manner as to require a minimum quantity or the high speed'tool steel and also in such a condition as to preserve and utilize to the utmost the very desirable metal cutting properties and durability thereof.

The end of the tool body remote from the chuck. end is provided with a plurality of long parallel sided grooves or slots l6 extending axially therein and suitable ior'snugly receiving a portion of the cutter elements." The portion of the tool body I3. of larger diameter, is cut down along one side of each groove 18 providing a listtened surface ll. Each metal cutter element l is an elongated strip of uniform thickness and having one edge shaped to present a suitable metalcutting edge is.

In accordance with my invention I provide in a side surface of the cutter elementone or more locking recesses or cut out portions suitablyformed for receiving metal'swagedfrom the tool body and for locking firmly therewith to secure and lock the cutting element permanently in the tool body. Locking recesses in the side of the cutter; element H are preferably short slots l9,

out axially" or longitudinally in the side of the element in any suitable manner, as by means or a small milling cutter for example. Such short locking slots is present sharp cornered edges 20 which efiectively interlock with the metal from the tool body preventing radial displacement of the element in a manner to be subsequently described.

Also-to firmly resist axial movement of the cutter element H in the tool body, each cutter ele- I ment is provided with a short slot 23 cut radially in the side of the element. The slot 23 presents sharp cornered edges 25 and 211 for respectively locking firmly with body metal to resist l 81- tudinal or axial movement of the cutter element in either respective direction.

A plurality of such short slots I9 and 23 are preferably proafter being recessed and sharpened.

In making such a'tool, one of the recessed cutter elements II is inserted and pressed snugly into each elongated groove It in the tool body.

By means of any suitable tool 29, such as a hammered hand tool, or a roller, 2. high pressure-is applied to the tool body along the flattened side ll of each elongated groove l8 adJacent the recessed side of the cutter element ll therein inserted. ,This swages the metal of the tool body and causes it to fiow into snug abutting engage ment with the side of the cutter element H and also causes the metal to flow into the short slots I9 and 23 and to firmly interlock with the sharp groove being suitably conformed for receiving the edge portion of a cutter blade remote from the cutter edge, a cutter blade inserted into and snugly seated in each groove in the tool body with the cutting edge projecting therefrom, means firmly and permanently securing each cutter blade in unfused durable metal cutting condition inthe tool body consisting of body metal permanently deformed from one side of the groove in the tool body adjacent the slotted side of the blade for gripping the side surfaceof the blade and the permanently deformed metal projecting into the short axial slots and into the short radial slots in the side of the blade for locking the cutter blade or blades against radial or axial movements in the tool body.

2. The method of mounting a strip shaped metal cutting blade of high speed tor steel in a grooved tool body of softer metal in an unfused durable metal cutting condition which consists in, cutting oneor more short slots axially in one side of the blade, cutting one or more short slotsradially in the side of the blade, inserting. one

edge of the blade into the groove in the tool along the side of the groove adjacent the slotted sides! the blade such as to permanently deform cornered edges, as shown in Figs. 6, 7 and 8,

- holding firmly along the full blade length.

I have found that this method of, and con struction for, mounting the cutter elements H in the tool body I! secures these elements very firmly against movement radially or axially in either direction. The cutter elements are permaresharped and used up, and the same principles may be embodied in other tools besides 'rearners.

the body metal into gripping engagement with speed tool steel, each cutter blade being of an elongated striplike conformation and having one 5 edge thereof suitably formed to provide a cutting nently a part of the tool and may be repeatedly A tool so constructed has great durability and long life because the cutter elements of" high speed tool steel are mounted in unfused relation: in the tool body without having been exposed to the high temperatures from welding or brazing. It is apparent that within the scope of the invention, modifications and different arrange- I claim: 1. In combination in a metal cutting reamer, metal cutter blades of high speed tool steel, each cutter blade being of an elongated striplike con-' formation and having one edge thereof suitably formed to provide a cutting edge, a portion of a side surface of the blade having short slots edge, the side surface of each blade extending from the cutting edge having short slots out axially providing asharp corner edge to lock against radial movement and short' slots out radially to provide a sharp slot edge for locking the cutter blade against axial movement in one direction and an oppositely directed sharp slot each cuttervblade remote from the cutter edge,

cut axially providing a sharp comer edge to loci:

against radial movement and short slots cut radially to provide a sharp slot edge for locking the cutter blade against axial movement in one direction and an oppositely directed sharp slot edge for locking the cutting blade firmly against movement in an opposite axial direction, a tool body of a softer and cheaper metal than said edge'for locking the cutting blade firmly against movement in an opposite axial direction, a tool body of a softer and cheaper metal than said cutter blade, said tool body being of an elongated generally .cylindrical'mnformation adapted to be rotated, one end of said tool body being adapted to be inserted and gripped in a chuck or other suitable turning mechanism, the other portion of said tool body being provided with parallel sided grooves extending axially therein and suitably conformed for receiving the edge portion of a cutter blade inserted into and snugly'seated in each groove in the tool body with the cutting edge projecting therefrom, means firmly and permanently securing each cutter blade in the tool body in a durable unfused condition consisting of body metal permanently deformed from one side of the groove in the tool body adjacent the slotted side of the blade for gripping the side surface of the blade and the permanently deformed metal projecting into the short axial slots and into the short radial slots in the side of the blade. for locking the cutter blade or blades against radial or axial movements in the tool body.

OSCAR A. PALM. 

